Visual impairment is the most common sensory problem of older adults. About 95% of individuals age 65 and older report wearing glassing or needing glasses to improve their vision. However, the effectiveness of glasses decreases with age. Among those over age 85, only 45% report that their glasses corrected all their visual problems and 12% are legally blind. Older adults should have vision checkups every two years if they wear glasses, every five years if they don't. Those with a family history of eye disorders, diabetes or a diagnosed vision disorder such as glaucoma or cataracts should get more frequent checkups.

Beginning in your 30s there is a decrease in the ability of your eyes to produce tears. Dry eyes can be made more comfortably by using "artificial tears" solutions. As you age, the pupil decreases in size, by age 60 it is about 1/3 the size it was when you were 20. The pupil may respond to darkness or bright lights by changing in size more slowly. The lens of the eye becomes yellowed, more rigid, and slightly cloudy. The iris--colored part of the eye- becomes more rigid over time.

Some of the major normal aging changes in the eye that affect vision include the following:

Corneal Flattening. In the aging eye the corneal surface flattens, admitting less light into the eyeball. This change reduces the transmitted light into the elderly eye by one third.
Lens Transparency. The transparency of the lens actually diminishes with aging which weakens available light to receive colors with short wavelengths such as blue and violet. When new lens fibers naturally multiply at the edge of the lens, older fibers move to the center to create a dense center of the lens. Over time, the lens accumulates yellow substances which filter out the blue part of the color spectrum. Blue actually appears more green. Warmer colors like reds and oranges, seem stronger in comparison.
Less Efficient Retina. The most sensitive part of the retina gradually functions less well with age due to decreased blood supply and the cumulative effects of radiation damage. The result is decreased spatial discrimination, black and white contrast, and flicker sensitivity. You become less able to tolerate glare and have more trouble adapting to darkness or bright light.
Reduced Lens Elasticity. Over time the lens of the becomes less elastic which diminishes the focusing power of the eye and causes a decline in visual acuity. This changes is usually first noticed around age 40 and is called presbyopia. As presbyopia becomes more pronounced, people hold reading materials further away from their eyes. Some get headaches or "tired eyes" while reading or doing other close work. By age 55, most people require glasses for reading at least part of the time. Those who already wear glasses may need bifocals. Fortunately, only 5% become unable to read and about 20% have enough visual impairment to prevent driving.